Power for use in a downhole environment has generally in the past been either stored in a battery and conveyed downhole or the power has been transmitted via conductors, such as a wireline, from the space or another remote location. Batteries have the capability of storing only a finite amount of power therein and have environmental limits, such as temperature, on their use.
Electrical conductors, such as those in a conventional wireline, provide a practically unlimited amount of power, but require special facilities at the surface for deployment. These facilities typically block the production flow path (i.e., limiting the flow rate of fluids through the flow path) while the conductors are in the flow path. Thus, wireline operations are typically carried out prior to the production phase of a well or during remedial operations after the well has been placed into production.
In wellbore drilling operations, one or more efficient power sources are desirable to power downhole instrumentation. A wide variety of devices can use mechanical energy in order to perform work downhole. Those devices may be subject to a variety of forces and can release energy in a number of ways.
A need exists for a system of harvesting mechanical energy downhole and generating electrical power therefrom. A need exists for a system to harvest energy in a wellbore containing a drill string.
The present embodiments meet these needs.
The present embodiments are detailed below with reference to the listed Figures.